Steam-generating pad

ABSTRACT

A steam-generating unit that is applied to the skin or the mucous membranes has a steam-generating part that employs chemical energy, and the surface applied to the skin or mucous membranes is made from a moisture-permeable sheet. The temperature of the steam generated by the steam-generating part and released from the surface of the steam-generating unit is kept to 50° C. or lower. Steam that is as safe as that from a steam towel can be easily and continuously supplied to the skin and mucous membranes by this steam-generating unit.

TECHNICAL FIELD

The present invention pertains to a steam-generating unit that providessteam to the skin of body parts, including the scalp, shoulders, neck,face, hips, buttocks, feet, hands, arms, etc., and mucous membranes,such as the eyes, nose, throat, etc., and thereby moistens these bodyparts and mucous membranes. In particular, the present inventionpertains to a steam-generating unit with which it is possible toefficiently percutaneously absorb drug and cosmetic components throughsteam and heat when it is used patched to the skin.

BACKGROUND ART

Facial saunas, steam towels, etc., are being used to provide steam thathas been optimally heated to the skin and thereby promote skincirculation and keep the skin in the desired moisturized state, orimprove the moisturized state of the skin.

Nevertheless, facial saunas and steam towels cannot always be used atany time and at any place. Moreover, it is difficult to use facialsaunas for any part of the body other than the face. Furthermore, steamtowels also pose a problem in that the time for which they can providesufficient steam is short.

The method whereby steam is generated using an electric heater orultrasonic waves is also a method of providing steam. However, thismethod cannot always be used everywhere. Moreover, there are alsomethods that employ chemical energy, such as the heat of neutralizationof acids and alkalis, the heat of hydration of inorganic salts, the heatof oxidation of metal powders, such as iron powder, etc., but sincetemperature of the steam that is generated is not controlled, even ifthese methods are simply used, there is a problem in terms of safetywhen they are directly used on the body.

The purpose of the present invention is to make it possible to easilyand continuously provide steam that is just as safe as that from a steamtowel to the skin and mucous membranes in response to these types ofproblems with background art.

DISCLOSURE OF THE INVENTION

In order to accomplish the above-mentioned purpose, the presentinvention presents a steam-generating unit, characterized in that it isa steam-generating unit that has a steam-generating part that useschemical energy and that is suitable for application to the skin andmucous membranes, and in that the temperature of steam that is releasedfrom the surface of said steam-generating unit is kept to 50° C. orLower.

As a preferred mode of the above-mentioned type of steam-generatingunit, a steam-generating unit where the amount of steam released fromthe surface of the steam-generating unit applied to the skin or mucousmembranes is 0.01 mg/cm²·min or more, particularly 0.5 mg/cm²·min ormore is presented.

Moreover, a mode of the above-mentioned type of steam-generating unitwhere cosmetic component or drug is placed on its surface or on theinside, and a mode where an adhesive layer is formed on the surface ofthe steam-generating unit that will be patched to the skin is presented.

The steam-generating unit of the present invention uses chemical energyin its steam-generating part and therefore, when compared to the casewhere steam is generated with a facial sauna, an electric heater orultrasonic waves, moisture and heat can be provided to the skin andmucous membranes of any part of the body, easily and at any time.Furthermore, since the temperature of the steam that is released fromthe surface of the steam-generating unit is kept at 50° C. or lower, itcan be used comfortably and safely.

Moreover, a sufficient amount of steam can be provided to the skin andthe mucous membranes by the mode where the amount of steam that isreleased from the surface of the steam-generating unit applied to theskin or mucous membranes is kept at 0.01 mg/cm²·min or more, preferably0.5 mg/cm²·min or more.

Furthermore, by means of the mode whereby there is a cosmetic componentor drug at the surface or inside the steam-generating unit and thiscosmetic component or drug is released with the steam, the skin can bemore quickly moisturized by the steam that is provided from thesteam-generating unit than the moisture that is provided by simpleperspiration, and penetration of the cosmetic component or drug to theskin is promoted, and the moisturized state is retained for a longperiod of time, enhancing the effects of these cosmetic components anddrugs.

In addition, by means of the mode where an adhesive layer that makes itpossible to patch the steam-generating unit to the skin is formed, aseparate holder, etc., is not necessary when the steam-generating unitis used on the skin and therefore, the steam-generating unit can be veryeasily used.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a top view of the steam-generating unit and

FIG. 1B is a cross section of it.

FIG. 2A is a top view of the steam-generating unit and

FIG. 2B is a cross section of it.

FIG. 3A is a top view of the steam-generating unit and

FIG. 3B is a cross section of it.

FIG. 4A is a top view of the steam-generating unit and

FIG. 4B is a cross section of it.

FIG. 5A is a top view of the steam-generating unit and

FIG. 5B is a cross section of it.

FIG. 6A is a top view of the steam-generating unit and

FIG. 6B is a cross section of it.

FIG. 7 is a top view of the steam-generating unit.

BEST MODE FOR CARRYING OUT THE INVENTION

The present invention will now be explained in detail.

The steam-generating unit of the present invention is used on the skinof the parts of the body, such as the scalp, shoulders, neck, face,hips, buttocks, feet, hands, arms, etc. and mucous membranes, such asthe eyes, nose, throat, etc.

Here, applying the steam-generating unit to the skin or mucous membranescan mean both bringing the steam-generating unit into contact with theskin or mucous membranes by patching the steam-generating unit to theskin or mucous membranes, and placing the steam-generating unit close tothe skin or mucous membranes without making contact.

Moreover, the steam that is released from the steam-generating unit ofthe present invention can be both gasified water and fine waterdroplets.

One characteristic of the steam-generating unit of the present inventionis that chemical energy is used in the steam generating part.

Heat of neutralization of acids and alkalis, heat of hydration ofinorganic salts (calcium chloride, magnesium chloride, calcium oxide,magnesium oxide, zeolite, etc.), heat of oxidation of metal powder,etc., can be mentioned as the chemical energy here.

The actual mode of use of said chemical energy in the steam-generatingpart is determined as needed in accordance with the type of reaction ofthe chemical energy that will be used. For instance, when the heat ofneutralization of an acid and an,alkali or the heat of hydration of aninorganic salt, etc., is used, the steam generating part can beconstructed from a heating part that generates the heat ofneutralization or heat of hydration and a vaporizing part where steam isreleased by the heat generated from the heating part. In this case, theheating part can be made so that the reactants themselves that are toreact are separated by a partition and whenever steam is generated, thispartition is broken down so that the reaction will proceed. Moreover,the vaporizing part is, for instance, made from a fiber aggregate ofpaper, fabric, nonwoven fabric, etc., or a porous material impregnatedwith water so that steam is released when heat is generated by theheating part.

Of the modes of using chemical energy, the mode where the exothermicbody itself releases steam is preferred because a vaporizing part thatis separate from the heating part is not needed. An example of this is asteam-generating composition that comprises metal powder, salt, andwater and releases steam with oxidation of the metal powder. In moreconcrete terms, for instance, iron powder goes through an exothermicreaction as shown by the following formula

Fe+(3/4)O₂+(3/2)H₂O→Fe(OH)₃+96 kcal

to release the water within the system as steam.

This type of exothermic reaction by metal powder is used in what iscalled a chemical pocket heater. General chemical pocket heaters areconstructed basically as heat tools and therefore, there are concernsabout whether they will have optimal gas permeability and whether thewater needed for the reaction will not escape from them. Therefore, bagsholding exothermic composition of chemical pocket heaters have gaspermeability, but in the end, they are not made from a sheet that ismoisture permeable. For instance, a sheet with a moisture permeabilityof 100˜400 g/m²·24 h by ASTM methods (Method E-96-80D) is used inJapanese Patent Laid-Open No. 1-250252. In contrast to that, since thesteam-generating composition of the present invention is ultimately usedas steam generation source, the surface that is applied to the skin ormucous membranes is made from sheet with a moisture permeability ofpreferably 4,000 g/m²·24 h or more, more preferably 8,000 g/m²·24 h ormore, and therefore, the method of using the steam-generatingcomposition of the present invention is very different from the methodwhereby the same composition in the conventional chemical pocket heatersis used.

Furthermore, it is a known fact that steam is released to outside thesystem with the exothermic reaction of the above-mentioned composition,and exothermic units for curling hair that use these steam-generatingeffects and heating effects (Japanese Patent Laid-Open No. 62-172907)are common. Nevertheless, the temperature of the steam that is to bereleased during the exothermic reaction by the above-mentionedcomposition becomes 60° C. or higher when it is exposed to theatmosphere, or almost exposed to the atmosphere, because the amount ofair that passes to the composition cannot be controlled. If the subjectof application is hair, there is no problem with steam that is 60° C. orhigher, but the skin and mucous membranes may be damaged by steam at 60°C. or higher provided continuously. Therefore, by means of the presentinvention, steam that is kept at 50° C. or lower is provided to the skinand mucous membranes.

By means of the present invention, this type of temperature control isalso performed when chemical energy in the form of the above-mentionedheat of neutralization of acids and alkalis, heat of hydration ofinorganic salts, etc., is employed.

Furthermore, in order to keep the temperature of the steam that isreleased from the steam-generating unit at 50° C. or lower, thetemperature of this steam is determined under atmosphere at roomtemperature (25° C., 65% RH), by placing the steam-generating unit withits steam-generating surface facing up on a pedestal of expandedpolystyrene, setting the detector of a temperature gauge (ThermorecorderRT-10 made by Tabaiesupekku Co., Ltd.) on this surface so that weightis-not applied to the steam-generating unit, and determining thetemperature at the surface of the steam-generating unit for 15 minutes.

Moreover, by means of a different method, temperature is determined inaccordance with the method of determining the temperature of disposablepocket heaters of JIS S4100, which is more resemble to an actual system.This temperature determination method shows a temperature that is higherthan the temperature obtained by the above-mentioned determinationmethod, as will be shown in the following examples, and therefore, thetemperature of the steam that is released from the surface of thesteam-generating unit is kept at 50° C. or lower in this case as well.

One mode of temperature control is a temperature-regulating materialplaced between the steam-generating part and the surface of thesteam-generating unit so that the steam released from thesteam-generating part passes through the temperature-regulating materialand the steam temperature is reduced. Controlling temperature with atemperature-regulating material is preferred because temperature of thesteam that is released from the surface of the steam-generating unit canbe reliably and simply controlled to 50° C. or lower, regardless of theform of chemical energy that is used in the steam-generating part.Furthermore, since the temperature-regulating material also resists thepassage of steam, the material used for the temperature-regulatingmaterial and its thickness, etc., is selected so that the desired amountof steam will be released from the surface of the steam-generating unitwhen temperature is controlled by using a temperature-regulatingmaterial.

Another mode of controlling temperature is to make a space between thesteam-generating part and the site on the skin or mucous membranes towhich the steam-generating unit is applied. This type of space should bemade so that there is a distance of 5 mm or longer between the steamgenerating part and the skin or mucous membrane. If this distance isless than 5 mm, temperature control is likely to be insufficient and theskin or mucous membranes might be burned. This type of space can beformed by a plastic molded body, etc., with good shape retention.

Other modes for temperature control can be selected as needed inaccordance with the reaction of the chemical energy in thesteam-generating part, etc. For example, reaction speed adjusted byvarying the amount of reactants that react at the steam-generating partand the particle diameter when the reactants are particles, etc., andthereby controlling the temperature of the steam that is released fromthe steam-generating unit surface.

In more concrete terms, when a steam-generating composition thatutilizes the heat of oxidation of iron powder at the; steam-generatingpart is used, in order to control the temperature of the steam that isreleased from the steam-generating unit surface at 50° C. or lower, thepreferable amount of iron powder present per 1 cm² surface of thesteam-generating unit which is applied to the skin or mucous membranesdepends on the particle diameter, specific surface area, etc., of theiron powder. 0.1 g/cm² or less is preferred when the iron powder for ageneral chemical pocket heater is used.

In terms of the effect of providing steam to the skin and mucousmembranes, the amount of steam that is released from the surface of thesteam-generating unit applied to the skin or mucous membranes should be0.01 mg/cm²·min or more, particularly 0.5 mg/cm²·min or more in thepresent invention. Furthermore, this amount of steam released iscalculated by the following formula, where Wt₀ (g) serves as weight whenthe determinations are started, Wt₁₅ (g) serves as weight after 15minutes, and S (cm²) serves as the surface area of the part where thesurface of the steam-generating unit is applied to the skin or mucousmembranes, when the steam-generating unit is placed directly on atop-pan scale capable of measuring up to 1 mg units under atmosphere ina room temperature environment (20° C., 65% RH) and weight is determined15 minutes later.

Amount of steam released (mg/cm²·min)

=(Wt ₀ −Wt ₁₅)·1000/15S  (1)

In order to bring the amount of steam that is released from the surfaceof the steam-generating unit applied to the skin or the mucous membranesto 0.01 mg/cm²·min or more, particularly, 0.5 mg/cm²·min or more, thesurface of the steam-generating unit applied to the skin or mucousmembranes is made from a moisture-permeable sheet. The moisturepermeationiby ASTM methods of this moisture-permeable sheet should be4,000 g·m²·24 h or more, preferably 8,000 g/m²·24 h or more.

A preferred mode of the present invention is described below in detailwhile referring to the figures. The same symbols represent the same oridentical structural elements in each of the figures.

FIGS. 1A and 1B are a top view and its x—x cross section of asteam-generating unit 10A of one mode of the present invention where atemperature-regulating material has been placed in between thesteam-generating part and the surface of the steam-.generating unit inorder to keep the temperature of the steam released from the surface ofthe steam-generating unit at 50° C. or lower.

This steam-generating unit 10A comprises a steam-generating part 2 wherea steam-generating composition 1 is held inside a moisture-permeableinner bag 2 i, a temperature-regulating material 3 piled on thesteam-generating part 2, a moisture-permeable outer bag 4 holding all ofthese, and further outside of these, a sealed bag 5 in which these aresealed.

This steam-generating unit 10A is used by tearing the sealed bag 5 atthe time of use and taking out its contents and applying thesteam-generating surface 4 a of this moisture-permeable outer bag 4 tothe skin or mucous membranes.

Here, steam-generating composition 1 held inside the moisture-permeableinner bag 2 i is made from a composition containing the same metalpowder (iron, aluminum, zinc, copper, etc.), salts (sodium chloride,potassium chloride, calcium chloride, magnesium chloride, etc.) andwater as the exothermic composition used for conventional chemicalpocket heaters by conventional methods and generates steam as a resultof the oxidation reaction of the metal powder. Of these, iron powder ispreferred as the metal powder in terms of economics, reactivity andsafety. Moreover, the steam-generating composition 1 can also contain avariety of components, such as moisture-retaining agents (vermiculite,calcium silicate, silica gel, silica porous substances, alumina, pulp,wood powder, water-absorbing polymers, etc.) and reaction promoters(activated carbon, carbon black, graphite, etc.), etc.

The amount of steam-generating composition 1 held inside themoisture-permeable inner bag 2 i is determined as needed in accordancewith the desired amount of steam release and the steam temperature.

The surface on at least the side of the moisture-permeable inner bag 2 ithat touches the body (steam-generating surface 2 a) is made from amoisture-permeable sheet. A sheet with a moisture permeation by ASTMmethods of preferably 4,000 g/m²·24 h or higher, more preferably 8,000g/m²·24 h or higher, from which the steam-generating composition 1 willnot leak is used as the moisture-permeable sheet.

Actual examples are fabric, nonwoven fabric, paper, synthetic paper,etc., of one or a mixture of two or more selected from artificialfibers, such as nylon, vinylon, polyester, rayon, acetate, acrylic,polyethylene, polypropylene, polyvinyl chloride, etc., and naturalfibers, such as pulp, cotton, flax, silk, animal hair, etc. Moreover,gas impermeable films or sheets (such as polyethylene, polypropylene,polyamide, polyester, polyvinyl chloride, polyvinylidene chloride,polyurethane, polystyrene, ethylene-vinyl acetate copolymersaponification product, ethylene-vinyl acetate copolymer, naturalrubber, rebuilt rubber, synthetic rubber, etc.) with micropores can alsobe used.

On the other hand, a surface 2 b on the opposite side of thesteam-generating surface 2 a of the moisture-permeable inner bag 2 i ofthis steam-generating unit 10A is made from a moisture-impermeablematerial. By making one side 2 b of the moisture-permeable bag moistureimpermeable in this way, it is possible to keep the steam that has beenreleased from the steam-generating composition 1 dispersing in theregulated direction so that the steam will pass through thesteam-generating surface 2 a and be effectively guided toward the body.

This moisture-impermeable surface 2 b is affixed to a nonwoven 3 a asthe anchoring tool and the moisture-permeable inner bag 2 i is therebyanchored.

The temperature-regulating material 3 piled on the steam-generatingsurface 2 a of the moisture-permeable inner bag 2 i is placed so thatthe temperature of the steam released from the steam-generatingcomposition 1 at the surface of the steam-generating unit 10A (a surface(steam-generating surface 4 a) of the moisture-permeable outer bag 4 onthe side applied to the skin or mucous membranes) is held at 50° C. orlower, preferably 45° C. or lower, particularly 38 to 42° C., withreliability and stability. At least one of (1) fabrics or nonwovenfabrics and (2) papers, such as paper, synthetic paper, etc., given asexamples of the moisture-permeable material of the moisture-permeableinner bag 2 i, as well as (3) porous films or porous sheets made fromplastic, natural rubber, rebuilt rubber, and synthetic rubber, (4)foamed plastics, such as urethane foam, etc., with through holes, and(5) metal foils, such as aluminum foil, etc., with through holes can beused as the structural material for this temperature-regulating material3.

The temperature-regulating material 3 also has a moisture permeabilityby ASTM methods of preferably 4,000 g/m²·24 h or more, more preferably8,000 g/m²·24 h or more, from which the steam-generating composition 1will not leak out.

Thickness of the temperature-regulating material 3, each of thestructural element materials forming the temperature-regulating material3, their combined state when several structural elements are piled, thepiling method, etc., are determined so that a specific amount of steamat a specific, temperature can be applied to the skin or mucousmembranes.

For instance, as shown in FIG. 1B, by piling 4 pieces of nonwoven 3 aand 2 pieces of paper 3 b as the temperature-regulating material 3, thedesired temperature control is achieved.

In place of the above temperature-regulating material 3, themoisture-permeable inner bag 2 i may have additional function same asthe temperature-regulating material 3.

The moisture-permeable outer bag 4 holds all of the above-mentionedmoisture-permeable inner bag 2 i and the temperature-regulating material3, and an adhesive layer 9 is placed to the end of the surface(steam-generating surface 4 a) of the moisture-permeable outer bag 4 onthe side applied to the skin or mucous membranes. Thus, it is possibleto easily fix the steam-generating unit 10A to the body when thesteam-generating unit 10A is applied to the body.

FIGS. 2A and 2B show the top view and the cross section of asteam-generating unit 10B of the present invention with a mode differentfrom the above-mentioned. This steam-generating unit 10B has a layer(referred to below as a drug layer 7) containing cosmetic components ordrugs, such as moisturizer, poultice, anti-inflammatory, exfoliatingagent, depilatory, etc., is placed on the surface of themoisture-permeable outer bag 4 that comes into contact with the skinwhen this steam-generating unit 10B is applied to the skin. When thedrug layer 7 is made in this way, it is possible for the cosmeticcomponent or drug to effectively act on the skin with the steam andoptimal heat released from the steam-generating composition 1.Furthermore, the drug layer 7 will be moistened by perspiration from theskin. However, the steam that is released from the steam-generatingcomposition 1 will very quickly bring the drug layer 7 to a thoroughlymoist state when compared to the steam that is produced by perspirationfrom the skin and this moist state will be retained for a longer periodof time. Therefore, when compared to simply applying cosmetic componentsand drugs to the skin as with conventional poultices, or applyingcosmetic components or drugs to the skin in combination with a simpleexothermic unit that in the end does not provide steam, the release ofdrugs or cosmetic components from the drug layer 7 is increased by usingthis steam-generating unit 10B and these cosmetic components and drugscan work more effectively on the skin.

The moisturizer that forms the drug layer 7 here is, for instance, apolyol such as glycerin, etc., a ceramide, collagen, etc. When the druglayer 7 formed of these moisturizer is applied to the skin around theeyes, mouth, etc., that can easily wrinkle, the moisturizing activity ofthe moisturizer is enhanced by synergism of these moisturizers and thewater provided from the steam-generating composition 1 and texture ofthe skin becomes moist and supple.

Moreover, indomethacin and methyl salicylate, etc., can be mentioned asexamples of anti-inflammatories. Percutaneous absorption of theseanti-inflammatories are promoted by the water, heat and the hydratingeffects provided from the steam-generating composition 1. Consequently,it is possible to effectively improve myalgia, arthralgia, lumbago, etc.Of the anti-inflammatories, indomethacin is particularly preferred interms of the large improvement in percutaneous absorption in thepresence of steam.

Proteases, such as papain, etc., can be given as examples of exfoliatingagents. This protease can be fixed to the surface of themoisture-permeable outer bag 4 by conventional methods when the solidenzyme is prepared. The catalytic activity of this type of solidprotease is improved by the heat and moisture provided from thesteam-generating composition 1. Consequently, residual skin layers canbe removed from the elbows, knees, heels, etc.

Depilatory components such as calcium thioglycolate, etc., are examplesof depilatories. The steam that is provided from the steam-generatingcomposition 1 humidifies and softens the area around the hair root andtherefore, by using depilatory in this way, the pain that accompanieshair removal can be alleviated and better depilatory results than whenconventional depilatories are employed can be obtained.

The steam-generating unit 10B in FIGS. 2A and 2B differs from thesteam-generating unit 10A in FIGS. 1A and 1B in that it has the druglayer 7 and further, both of the steam-generating surface 2 a and thesurface 2 b on the opposite side, of the moisture-permeable inner bag 2i are made from a moisture-permeable material, and amoisture-impermeable sheet 6, for instance, a piled sheet ofethylene-vinyl acetate copolymer and polyethylene, is piled on thesurface 2 b on the opposite side of the steam-generating surface 2 a.Thus, dispersing of the steam that has been released from thesteam-generating composition 1 is prevented by using thismoisture-impermeable sheet 6 and the steam can pass through thesteam-generating surface 2 a of the moisture-permeable inner bag 2 i andbe more effectively guided toward the body.

FIGS. 3A and 3B are a top view and a cross section of a steam-generatingunit 10C of the present invention with yet another mode. Thesteam-generating units in above-mentioned FIGS. 1 and 2 used 4 pieces ofnonwoven 3 a and 2 pieces of paper 3 b piled together for thetemperature-regulating material 3, but in FIG. 3, two pieces of nonwoven(3 c, 3 d) are combined together and piled.

FIGS. 4A and 4B are a top view and a cross section of a steam-generatingunit 10D of the present invention of still a different mode. In theabove-mentioned 3 steam-generating units 10A, 10B and 10C, the heat ofoxidation of metal powder from a conventional chemical pocket heatercomposition is used in the steam-generating part 2, but the heat ofhydration of calcium chloride is used in the steam-generating part 2 ofthe steam-generating unit 10D of FIG. 4.

The steam-generating part 2 of this steam-generating unit 10D is madefrom a heating part 2 p and a vaporizing part 2 q. The heating part 2 pcomprises polyethylene film, which is water impermeable, and the insideis divided into 2 receptacles 2 c and 2 d. After introducing thecontents to these receptacles 2 c and 2 d, these 2 receptacles 2 c and 2d are pressed to be easily connected with one another at their boundaryregion 2 e. Calcium chloride is introduced to one of these (receptacle 2c), while water is introduced to the other (receptacle 2 d). Thevaporizing part 2 q is constructed by a nonwoven with a water-absorbedpolymer as the middle layer and placing this in a nonwoven inner bagmade from moisture-permeable and water-impermeable polypropylene fibers.

FIGS. 5A and 5B are a top view and a cross section of a steam-generatingunit 10E of one mode of the present invention where there is space 11 inbetween the steam-generating part and the part applied to the skin ormucous membranes in order to control the temperature to 50° C. or lower.The same steam-generating part 2 of the steam-generating unit 10E as inFIG. 1 is used. A support 8 of the space 11 is made from a cylindricalpolypropylene molded article. One end, 8 a, is placed to thesteam-generating part 2, while the other end 8 b is patched to the skinor mucous membranes by adhesive layer 9. Height h of the cylinder of thesupport 8 should be 5 mm or higher. If height h is under 5 mm,temperature control will be insufficient and burns may occur.

FIGS. 6A and 6B are a top view and a cross section of yet anothersteam-generating unit 10F of the present invention. The amount of ironpowder that is present per 1 cm² surface of the steam-generating unitapplied to the skin or mucous membranes is low in this steam-generatingunit 10F when compared to above-mentioned steam-generating unit 10A(FIG. 1), 10B (FIG. 2), 10C (FIG. 3), and 10E (FIG. 5) and therefore,the temperature of the steam at the surface of the steam-generating unit10F is kept to 50° C. or lower without placing a temperature-regulatingmaterial or space between the skin or mucous membranes and thesteam-generating part 2 when it is applied to said skin or mucousmembranes.

FIG. 7 is a top view of yet another steam-generating unit 10G of thepresent invention. By means of the above-mentioned steam-generating unit10A (FIGS. 1A and 1B), almost the entire surface is placed on thesteam-generating part 2, but by means of the steam-generating unit 10Gof FIG. 7, several steam generating parts 2 are placed with a spacebetween steam-generating parts 2, inside the steam-generating unit 10G.Thus, it seems that even if steam-generating parts 2 are placed with aspace inside the steam-generating unit 10G, steam is generated andcosmetic component or drug is released almost uniformly from thesteam-generating unit 10G.

Consequently, in the steam-generating unit of the present invention,there are no special restrictions to the position of thesteam-generating parts inside the steam-generating unit.

Various modes of the present invention other than those illustratedabove can be used as long as the temperature of the steam released fromthe steam-generating unit surface is controlled to 50° C. or lower. Forinstance, by means of the steam-generating unit 10B in FIGS. 2A and 2B,the drug layer 7 containing cosmetic component or drug is placed at theouter surface of the moisture-permeable outer bag 4, but the drug layer7 can also be placed between the steam-generating part 2 and themoisture-permeable outer bag 4. Moreover, the adhesive layer 9 on themoisture-permeable outer bag 4 can be formed over one entire side of themoisture-permeable outer bag 4, and cosmetic component or drug can alsobe contained in the adhesive layer 9.

EXAMPLES

The present invention is described below in concrete terms withexamples.

Example 1

The steam-generating unit 10A of the mode in FIGS. 1A and 1B was made asfollows:

First, 5 g of a mixture of 1 part by weight water-absorbing polymer(Nihon Shokubai Co., Ltd., brand name: Aqualik CA), 3 parts by weightsilica gel (Wako Junyaku Co., Ltd., brand name: Wakogel C-200), and 10parts by weight of aqueous 12.5 wt % sodium chloride solution and 10 giron powder (Dowa Teppun Kogyo Co., Ltd., brand name: RKH) were mixed toobtain the steam-generating composition 1.

Three grams of this steam-generating composition 1 were then packed intoa 3×3 cm² small square bag comprising a vinyl-coated sheet on one side(Nitto Denko Co., Ltd., brand name: Nitotack) and a sheet ofmoisture-permeable nonwoven (Mitsui Kagaku, brand name: Syntex MB, net:15 g/m²) on the other side.

This small bag was placed and anchored on its bottom surface to thenonwoven 3 a (Chisso Co., Ltd., brand name: Air-raid, net: 24 g/m²)served as the support, with the surface made from moisture-permeablenonwoven facing up. The temperature-regulating material 3 with the piledstructure in FIG. 1, that is, 1 layer of paper 3 b (Kreshia, brand name:Kimtowel), 2 layers of nonwoven 3 a (Chisso, brand name: Air-raid, net:24 g/m²), 1 layer of paper 3 b (Kreshia, brand name: Kimtowel), and 2layers nonwoven 3 a (Chisso Co., Ltd., brand name: Air-raid, net: 24g/m²) were piled in order, and the entire unit was then placed in themoisture-permeable outer bag 4 comprising moisture-permeable nonwoven(Mitsui Kagaku, brand name: Syntex MB, net: 15 g/m²). Then the entireoutside was sealed by an air-tight bag (sealed bag) 5 (Asahi KaseiPolyplex Co., Ltd., brand name: Hiryu) to obtain the steam-generatingunit 10A.

Example 2

A steam-generating unit 10B of the mode shown in FIGS. 2A and 2B wasmade as follows:

Three grams of the same steam-generating composition 1 as in Example 1were packed in a 3×3 cm² small square bag made from moisture-permeablenonwoven (Mitsui Kagaku, brand name: Syntex MB, net: 15 g/m²). Thissmall bag was placed and fastened to the moisture-impermeable sheet 6that was a pile of ethylene-vinyl acetate copolymer and polyethylene,and the temperature-regulating material 3 same as Example 1 (one layerof paper 3 b, 2 layers of nonwoven 3 a, 1 layer of paper 3 b, and 2layers of nonwoven 3 a piled in succession) were placed on the otherside and the entire unit was introduced to the outer bag 4 made frommoisture-permeable nonwoven (Syntex MB, net: 15 g/m²). An adhesive layer9 (Nichiban Co., Ltd., brand name: Nicetack) was placed around theperiphery of this surface and filter paper (the drug layer 7) holdingmethyl salicylate was set in the middle of this. The entire outside wassealed with the air-tight bag 5 (Asahi Kasei Polyflex, brand name Hiryu)to obtain the steam-generating unit 10B.

Example 3

A steam-generating unit 10C with the mode in FIGS. 3A and 3B was made asfollows:

Three grams of the same exothermic composition 1 as in Example 1 werepacked in a 3×3 cm² small square bag made from a vinyl coated sheet(Nitto Denko Co., Ltd., brand name: Nitotack) on one side and amoisture-permeable nonwoven (Mitsui Kagaku, brand name: Syntex MB, net:15 g/m²) on the other side. This small bag was placed and anchored onits bottom surface to the nonwoven 3 a (Chisso Co., Ltd., brand name:Air-raid, net: 24 g/m²) served as the support, with the surface of themoisture-permeable nonwoven facing up. Then the temperature-regulatingmaterial 3 with the piled structure in FIG. 3 (pile of 2 layers nonwoven3 c (Honshu Kinocloth Co., Ltd., brand name: Kinocloth KS-40) and 3 d(Nihon Bairin Co., Ltd., brand name; Baiwarm Airback KNF-350)) wasplaced on top of this and the entire unit was placed in outer bag 4comprising moisture-permeable nonwoven (Syntex MB, net: 15 g/m²). Theadhesive layer 9 (Nichiban Co., Ltd., brand name: Nicetack) was placedon parts of this surface and the entire unit was sealed on the outsidewith the air-tight bag 5 (Asahi Kasei Polyflex, brand name: Hiryu) toobtain the steam-generating unit 10C.

Example 4

A steam-generating unit 10D with the mode in FIGS. 4A and 4B was made asfollows:

Calcium chloride was introduced to one receptacle 2 c, of a bagcomprising polyethylene film, which is water impermeable, that had beenmade by dividing the inside into 2 receptacles 2 c and 2 d, as shown inFIG. 4, so that these 2 receptacles 2 c and 2 d can be easily connectedat a boundary 2 e when they are pressed, while water was introduced tothe other receptacle 2 d, to form the heating part 2 p. Nonwoven (HonshuKinocloth Co., Ltd., brand name: B-SAP85) impregnated with 20 g waterwas placed on top of the heating part 2 p as the vaporizing part 2 q.The temperature-regulating material 3 with the piled structure in FIG. 3(pile of nonwoven 3 c (Honshu Kinocloth Co., Ltd., brand name: KinoclothKS-40) and 3 d (Nihon Bairin Co., Ltd., brand name: Baiwarm AirbackKNF-350)) was further placed on top of this and the entire unit washoused in the outer bag 4 comprising moisture-permeable nonwoven (MitsuiKagaku, brand name: Syntex MB, net: 15 g/m²). The adhesive layer 9(Nichiban Co., Ltd., brand name: Nicestack) was placed on parts of thissurface and the entire unit was further sealed on the outside by theair-tight bag 5 (Asahi Kasei Polyflex Co., Ltd., brand name: Hiryo) toobtain steam-generating unit 10D.

Example 5

A steam-generating unit 10E of the mode in FIGS. 5A and 5B was made asfollows:

Three grams of the same steam-generating composition 1 as in Example 1were packed in a small round bag (the moisture-permeable inner bag 2 i)with a diameter of 30 mm comprising a vinyl coated sheet (Nitto Denko,brand name: Nitotack) on one side (2 b) and moisture-permeable nonwoven(Mitsui Kagaku, brand name: Syntex MB, net: 15 g/m²) on the other side(2 a). Then, with the vinyl-coated surface of this small bag facing up,polypropylene cylindrical molded article (the support 8) with a diameterof 30 mm and height (h) of 6 mm was placed on the bottom of the smallbag, and the adhesive layer 9 was further placed so that the productcould be patched to the skin or mucous membranes. The entire unit wasfurther sealed on the outside with the air-tight bag 5 (Asahi KaseiPolyflex Co., Ltd., brand name Hiryu) to obtain the steam-generatingunit 10E.

Examples 6 through 10

Steam-generating units 10F-1, 10F-2, 10F-3, 10F-4, and 10F-5 of the modein FIGS. 6A and 6B were made as follows:

The exothermic compositions in Table 1 were each prepared and then thesewere packed, in the amounts shown in Table 1, in a 5×5 cm² small squarebag comprising a gas-permeable composite sheet (Nitto Denko, brand nameBreslon 38) on one side and moisture-permeable nonwoven (Mitsui Kagaku,brand name: Syntex BM, net: 15 g/m²) on the other side. Amounts of ironpowder per 1 cm² surface of these steam-generating units are also listedin Table 1.

Furthermore, the entire unit was sealed on the outside with theair-tight bag 5 (Asahi Kasei Polyflex Co., Ltd., brand name: Hiryu) toobtain steam-generating units 10F-1, 10F-2, 10F-3, 10F-4, and 10F-5.

TABLE 1 Example 6 7 8 9 10 Steam-generating unit 10F-1 10F-2 10F-3 10F-410F-5 Composition (wt %) Iron powder^(*1) 33.3 25.0 25.0 31.7 28.6water-absorbing — — 9.4 15.7 8.9 polymer^(*2) Calcium silicate 16.7 18.89.4 8.1 8.9 micropowder Aqueous 15% sodium 50 56.2 56.2 44.5 53.6chloride solution Amount packed in 6.0 8.0 8.0 6.3 6.3 bag (g) Amount ofiron 0.080 0.080 0.080 0.080 0.072 powder (g/cm²) ^(*1)Dowa Teppun KogyoCo., Ltd., brand name: RKH ^(*2)Nihon Shokubai Co., Ltd., brand name:Aqualik CA

Evaluations

The steam-generating unit obtained in each of the examples was taken outfrom the air-tight bag 5 and maximum temperature of the steam releasedfrom the steam-generating unit surface (referred to below as maximumsteam temperature) was found in accordance with the temperaturedetermination method in JIS S4100 (method *3 in Table2). Furthermore, inExample 1, maximum temperature was also found by the above-mentionedmethod of setting the detector of a temperature gauge on the surface ofthe steam-generating unit (method *4 in Table2).

In addition, the amount of steam released per unit time and unit surfacearea by the steam-generating unit obtained from each Example was foundby above-mentioned formula (1). The results are listed in Table 2.

Moreover, the maximum steam temperature and amount of steam releasedwere also found for commercial chemical pocket heaters A, B and C andthe product of an example from Japanese Patent Laid-Open No. 62-172907as Comparative Examples 1 through 4. The results are listed in Table 2.

TABLE 2 Maximum Maximum Amount of steam steam steam temperaturetemperature released (method*3) (method*4) (mg/cm² · (° C.) (° C.) min)Example 1 (10A) 47 42 1.10 Example 2 (10B) 47 — 1.10 Example 3 (10C) 48— 1.67 Example 4 (10D) 48 — 0.83 Example 5 (10E) 49 — 1.98 Example 6(10F-1) 47 — 1.60 Example 7 (10F-2) 48 — 1.63 Example 8 (10F-3) 46 —1.43 Example 9 (10F-4) 46 — 1.33 Example 10 (10F-5) 44 — 0.80Comparative Example 1 50 — <0.01 (Commercial product A) ComparativeExample 2 46 — <0.01 (Commercial product B) Comparative Example 3 41 —<0.01 (Commercial product C)^(*5) Comparative Example 4 84 — 2.80(Japanese Patent Laid-Open No. 62-172907 Example product) ^(*5)Medicalheating tool that is patched directly to the skin.

As is clear from Table 2, almost no steam was generated by commercialchemical pocket heaters (Comparative Examples 1 through 3). Moreover,although steam was definitely generated by Comparative Example 4, themaximum steam temperature rose to 84° C. and therefore, it could not beused on the skin or mucous membranes. In contrast to this, the steamgenerated by the steam-generating units of the present invention was ata moderate temperature of 50° C. or lower and therefore, warm steam canbe easily provided to the skin and mucous membranes.

INDUSTRIAL APPLICABILITY

By means of the present invention, steam that is as safe as that from asteam towel can be continuously supplied to the skin and mucousmembranes by a simple structure that uses chemical energy.

What is claimed is:
 1. A steam-generating unit, comprising: i) a steam-generating part that uses chemical energy, ii) a moisture-permeable sheet; and iii) a temperature-regulating material disposed between said steam-generating part and said moisture-permeable sheet, wherein the amount of steam released from a surface of said steam-generating unit which is applied to skin or mucous membranes is 0.01 mg/cm²·min or more, and a temperature of said steam released from said surface of said steam-generating unit, is 50° C. or lower.
 2. The steam-generating unit according to claim 1, wherein the amount of steam released from the surface of the steam-generating unit applied to the skin or the mucous membranes is 0.5 mg/cm²·min or more.
 3. The steam-generating unit according to claim 1, wherein there is cosmetic component or drug at the surface or inside of the steam-generating unit and said cosmetic component or drug is released with the steam.
 4. The steam-generating unit according to claim 1, wherein an adhesive layer is formed on the surface of the steam-generating unit to be applied to the skin.
 5. The steam-generating unit according to claim 4, wherein cosmetic component or drug is contained in the adhesive layer.
 6. The steam-generating unit according to claims 1, wherein the steam-generating part comprises a steam-generating composition that contains metal powder, salts, and water, and that releases steam with oxidation of the metal powder.
 7. The steam-generating unit according to claim 6, wherein there is a structure of at least one of (1) fabric or nonwoven fabric, (2) paper, (3) porous film or porous sheet molded from plastic, natural rubber, rebuilt rubber, or synthetic rubber, (4) foamed plastic with through-holes, and (5) metal foil with through-holes, as the temperature-regulating material that keeps the temperature of the steam released by the steam-generating part to 50° C. or lower on the outside of the steam-generating part. 